OpenAI's Cursor deadline is today

Today is the day OpenAI said it plans to cut Cursor off.

OpenAI has told SpaceX it intends to wind down the contract that supplies its models to Cursor, with a "proposed shutoff date of November 12, 2026", today. The deadline is proposed, not confirmed as live: as of November 11, the two companies were still talking, trying to resolve the dispute. But the clock OpenAI set has now run out, and Cursor users who rely on OpenAI models are waiting to see what actually happens when the day arrives.

Background: the acquisition

OpenAI's decision follows SpaceX's acquisition of Anysphere, the company behind Cursor. SpaceX agreed in June 2026 to buy Anysphere for $60 billion in an all-stock deal, and the acquisition closed on August 14, 2026. Since then, Cursor has been a SpaceX-owned company, and OpenAI has decided it no longer wants to supply it.

OpenAI's stated rationale

In a statement published on its official blog, OpenAI was blunt about why. "We are making this choice because we cannot be confident that SpaceX will use our technology within our terms of service, based on our experience with Elon Musk's companies violating contracts."

That is unusually direct language from OpenAI, and it puts the dispute squarely in the open: this is not a technical disagreement or a pricing dispute. OpenAI says it does not trust that its technology would be used within the terms of the agreement once it is in the hands of a company owned by Elon Musk.

OpenAI also made clear the cutoff is not limited to the models Cursor uses today. The company said it will not provide future models to Cursor either, naming its upcoming model Astra among the models that will not be supplied. The door, in other words, is closing forward as well as backward.

The scale of the impact

The practical impact may be smaller than the headlines suggest. Cursor CEO Michael Truell has said that OpenAI models serve only about 5% of Cursor's traffic. The overwhelming majority of what Cursor users run already comes from other model providers, and that traffic is unaffected by OpenAI's decision.

Truell also confirmed that the two companies are still talking to resolve the situation, even as the proposed deadline arrives. The fact that talks were ongoing as of November 11 leaves open the possibility of a last-minute agreement, or at least a delay. What is not in doubt is that OpenAI has set a date and said it intends to act on it.

What stops working, and what does not

It is important to be precise about what ends if the shutoff goes ahead. What ends is the built-in, direct supply of OpenAI models inside Cursor, the models a user can select in the editor without any extra setup.

What does not end is everything else. Developers who bring their own OpenAI API key can keep using OpenAI models that way, and OpenAI's own IDE extensions keep working. The cutoff targets the direct commercial relationship between OpenAI and Cursor, not a developer's ability to use OpenAI's technology through their own key.

That distinction matters for the developers who do use OpenAI models inside Cursor. They have a workaround, but it is a workaround: a separate key, a separate billing relationship, and a different setup from the one-click experience Cursor sells.

Significance

Cursor is one of the most widely used AI coding tools in the world, and this is the first time a major model provider has publicly moved to cut off a leading coding assistant over the behaviour of its new owner. The dispute sits at the intersection of two of the biggest stories in technology: the race to build the best AI coding tools, and the rivalry between OpenAI and Elon Musk's companies.

The $60 billion acquisition was supposed to make Cursor part of SpaceX's growing AI ambitions. Instead, within three months of the deal closing, one of the industry's most important model suppliers has said it does not want to do business with the combined company. That is a signal to the whole market about how the Musk-OpenAI rivalry is now playing out in commercial contracts, not just in courtrooms and on social media.

It also raises a question every AI toolmaker will be watching: if a model provider can cut off a customer over who owns it, how secure is any AI product that depends on someone else's models? Cursor's answer, so far, is that its exposure is limited, only about 5% of its traffic runs on OpenAI models. Other tools that depend more heavily on a single provider may not be able to say the same.

What to watch

The immediate question is whether the proposed shutoff actually takes effect today, or whether the ongoing talks produce a delay or a deal. Neither company has confirmed that the models have gone dark. If the cutoff proceeds, the next question is whether Cursor users on OpenAI models notice the change at all, and whether the 5% figure holds up in practice, or whether the most demanding users are concentrated in that small slice.

Longer term, the episode may push Cursor further toward the model providers it already relies on for most of its traffic, and push the industry toward a world where the biggest AI tools are judged not only on their features, but on whose models they can still access. For OpenAI, the decision draws a line: its technology, it says, comes with terms, and it will walk away from a $60 billion company's business rather than supply a customer it does not trust to honour them.